The present invention is directed to integrated circuits and their processing for the manufacture of semiconductor devices. More particularly, the invention provides a method and system for forming contacts on integrated circuits. Merely by way of example, the invention has been applied to the annealing processes for the manufacture of integrated circuits. But it would be recognized that the invention has a much broader range of applicability.
Integrated circuits or “ICs” have evolved from a handful of interconnected devices fabricated on a single chip of silicon to millions of devices. Current ICs provide performance and complexity far beyond what was originally imagined. In order to achieve improvements in complexity and circuit density (i.e., the number of devices capable of being packed onto a given chip area), the size of the smallest device feature, also known as the device “geometry”, has become smaller with each generation of ICs. Semiconductor devices are now being fabricated with features less than a quarter of a micron across.
Increasing circuit density has not only improved the complexity and performance of ICs but has also provided lower cost parts to the consumer. An IC fabrication facility can cost hundreds of millions, or even billions, of dollars. Each fabrication facility will have a certain throughput of wafers, and each wafer will have a certain number of ICs on it. Therefore, by making the individual devices of an IC smaller, more devices may be fabricated on each wafer, thus increasing the output of the fabrication facility. Making devices smaller is very challenging, as each process used in IC fabrication has a limit. That is to say, a given process typically only works down to a certain feature size, and then either the process or the device layout needs to be changed. An example of such a limit is chemical dry etching process used for the manufacture of integrated circuits in a cost effective and efficient way.
The manufacturing of integrated circuits involves various processes. For example, the processes include, inter alia, wafer growth, photolithography, doping, oxidation, deposition, etching removal, contact deposition, and epitaxial growth.
One of the various processes is forming a electrical contacts for certain types of integrated circuits, such as DRAM cells. According to a conventional technique, electrical contacts are formed by coupling tungsten material and dielectric materials. Usually, it is desirable for the contact to be structurally stable and low-resistance. Various conventional techniques have been developed toward these goals. Unfortunately, conventional techniques are often inadequate.
Therefore, improved system and method for forming contacts for integrated circuit devices are desired.